Piloted poppet valve

Abstract

A valve assembly includes a valve body having a valve bore. A valve member is slidably disposed within the valve bore between first and second stop positions. First and second valve elements of the valve member have first and second sealing surfaces equally angled with respect to a valve member longitudinal axis. Each of the first and second sealing surfaces is oriented parallel with conical shaped first and second seat surfaces. Both first and second seat surfaces are equally angled with respect to the longitudinal axis and have an adjustable spacing such that the first sealing surface contacts the first seat surface and the second sealing surface contacts the second seat surface simultaneously in the first stop position.

What is claimed is: 
     
       1. A valve assembly, comprising:
 a valve body having a valve bore; 
 a valve member slidably disposed within the valve bore between first and second stop positions; 
 first and second radially extending valve elements connected to the valve member having first and second sealing surfaces oriented at equal angles with respect to a longitudinal axis of the valve member; 
 the first and second sealing surfaces being oriented substantially parallel with conical shaped first and second seat surfaces positioned in the valve body, both first and second seat surfaces oriented at equal angles with respect to the longitudinal axis and having an adjustable spacing such that the first sealing surface contacts the first seat surface and the second sealing surface contacts the second seat surface simultaneously in the valve member first stop position; and 
 first and second pistons positioned at opposite ends of the valve member each having only a single bore seal in each of the first and second pistons adapted to create a sliding seal. 
 
     
     
       2. The valve assembly of  claim 1 , wherein the first valve element includes a third sealing surface and the second valve element includes a fourth sealing surface, the third and fourth sealing surfaces defining mirror image orientations with respect to the first and second sealing surfaces, the third and fourth sealing surfaces oriented parallel to each other and each oriented at substantially equal angles with respect to the longitudinal axis of the valve member. 
     
     
       3. The valve assembly of  claim 2 , further including conical shaped third and fourth seat surfaces each adapted to be contacted by one of the third and fourth sealing surfaces, both third and fourth seat surfaces oriented at equal angles with respect to the longitudinal axis and oriented parallel to the third and fourth sealing surfaces of the valve elements such that the third sealing surface contacts the third seat surface simultaneously with the fourth sealing surface contacting the fourth seat surface in a second stop position of the valve member. 
     
     
       4. The valve assembly of  claim 1 , further including:
 a solenoid assembly connected to the valve body and adapted to communicate with pressurized air; and 
 a solenoid member slidably positioned in the solenoid assembly adapted to change flow alignment of selected ones of first, second, and third ports of the solenoid assembly to direct the pressurized air to either the first or second piston to axially translate the valve member toward the first stop position or oppositely toward a second stop position of the valve member. 
 
     
     
       5. The valve assembly of  claim 1 , further including first and second adapters each selectively co-axially positioned with respect to the longitudinal axis and each including one of the first and second seat surfaces. 
     
     
       6. The valve assembly of  claim 1 , wherein the first and second valve elements are over-moldings of a resilient material molded onto the valve member, the first valve element adapted to seal against the first seat surface defining a first perimeter contact surface area and the second valve element adapted to seal against the second seat surface creating a second perimeter contact surface area equal to the first perimeter contact surface area. 
     
     
       7. The valve assembly of  claim 1 , wherein the valve body further includes a fluid inlet port in fluid communication with a source of fluid, first and second outlet ports, and first and second exhaust ports, wherein the first and second outlet ports communicate with the inlet port via the valve bore such that the inlet port is in fluid communication with the first outlet port in the first stop position of the valve member and the inlet port is in fluid communication with the second outlet port in a second stop position of the valve member. 
     
     
       8. The valve assembly of  claim 1 , wherein a surface area of the first valve element in contact with the first seat surface is substantially equal to a surface area of the second valve element in contact with the second seat surface in the first stop position. 
     
     
       9. A valve assembly, comprising:
 a valve body having an axially extending valve bore; 
 a valve member slidably disposed within the valve bore between first and second stop positions; 
 first and second resilient valve elements connected to the valve member, the first valve element having a first sealing surface and the second valve element having a second sealing surface, the first and second sealing surfaces oriented at equal angles with respect to a longitudinal axis of the valve member, the first valve element further including a third sealing surface and the second valve element further including a fourth sealing surface; 
 the first sealing surface adapted to contact a conical shaped first seat surface defining a first perimeter contact surface area, and the second sealing surface adapted to contact a conical shaped second seat surface defining a second perimeter contact surface area equal to the first perimeter contact surface area, the first and second seat surfaces oriented substantially parallel to the first and second sealing surfaces, a spacing between the first and second seat surfaces being equal to a spacing between the first and second sealing surfaces providing for simultaneous contact between the first sealing surface and the first seat surface and between the second sealing surface and the second seat surface in the first stop position; 
 third and fourth seat surfaces oriented parallel to each other and oriented at substantially equal angles with respect to the longitudinal axis of the valve member; 
 an equal surface area of contact created between the first and second resilient valve elements with respect to the seat surfaces in both the first and second stop positions; and 
 first and second pistons positioned at opposite ends of the valve member each having a bore seal member and a resilient material centering bore seal having a conical tipped perimeter portion, the perimeter portion contacting first and second cylinder walls to center the first and second pistons with respect to a longitudinal axis of the valve member. 
 
     
     
       10. The valve assembly of  claim 9 , wherein the third and fourth sealing surfaces define mirror image orientations with respect to the first and second sealing surfaces. 
     
     
       11. The valve assembly of  claim 10 , wherein the third and fourth seat surfaces have a spacing equal to a spacing between the third and fourth sealing surfaces. 
     
     
       12. The valve assembly of  claim 10 , wherein the third and fourth seat surfaces are conical shaped and are each adapted to be contacted by one of the third or fourth sealing surfaces, both third and fourth seat surfaces oriented parallel to the third and fourth sealing surfaces providing simultaneous contact between the third sealing surface and the third seat surface and between the fourth sealing surface and the fourth seat surface when the valve member is positioned in the second stop position. 
     
     
       13. The valve assembly of  claim 10 , wherein the third sealing surface is adapted to contact the third seat surface defining a third perimeter contact surface area, and the fourth sealing surface is adapted to contact the fourth seat surface defining a fourth perimeter contact surface area equal to the third perimeter contact surface area. 
     
     
       14. The valve assembly of  claim 9 , further including at least one adapter slidably positioned within the valve bore between the valve member and the valve body and adapted to slidably receive the valve member, the at least one adapter axially movable to adjust a spacing between the first seat surface and the second seat surface. 
     
     
       15. The valve assembly of  claim 9 , wherein the valve body further includes an inlet port and first and second outlet ports, and wherein in the first stop position the valve member is adapted to selectively direct flow of a fluid from the inlet port through the valve bore to the first outlet port, and in a second stop position the valve member is adapted to selectively direct flow of the fluid from the inlet port through the valve bore to the second outlet port.